VARIOUS KINDS OF STRESS AND SMALL HEAT SHOCK PROTEIN, α-CRYSTALLIN mRNA EXPRESSION IN LENS EPITHELIAL CELLS

2004 Fiscal Year Final Research Report Summary

• Project/Area Number: 15591878
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Ophthalmology
• Research Institution: Tokyo Medical University
• Principal Investigator: USUI Masahiko Tokyo Medical University, Medicine, Professor, 医学部, 教授 (40074570)
• Co-Investigator(Kenkyū-buntansha): SUZUKI Jun Tokyo Medical University, Medicine, Assistant, 医学部, 助手 (90349449) ; YAGIHASHI Tomoyuki Tokyo Medical University, Medicine, Assistant, 医学部, 助手 (20328248)
• Project Period (FY): 2003 – 2004
• Keywords: α-crystallin / lens epithelial cells / cataract / heat shock protein

Research Abstract

α-crystallin is a heat shock protein with about 27 kd molecular weight (HSP27), and its heat tolerance is derived from HSP function. In this study, focusing on the role of a-crystallin in lens opacity and lens epithelial cells, we investigated mRNA expression of α-crystallin in lens epithelial cells obtained during surgery. Nineteen eyes with age-related cataract, and for the control, Six eyes from which the lens was removed during vitreous surgery in young patients were investigated. Anterior capsule was placed in Zol reagent to extract epithelial cell RNA. Furthermore, cDNA was prepared, and the expression level of a-crystallin mRNA (copies) was measured by real-time PCR using syber green 1. Primers were prepared based on Accession No NM_000394. For the control mRNA, GAPDH mRNA, was used, and the expression level was judged based on the normalized ratio (α-crystallin mRNA/GAPDH mRNA). The mean normalized ratio was 0.027in age-related cataract and 0.187 in the control, with a significant difference between the two groups (t-test, p=0.01). Decreased expression of α-crystallin in lens epithelial cells, i.e., decreased HSP function, may be involved in opacity formation in the lens.